This is an old question that is no longer in use.
Images may be missing and the information may be dated.
You arrive at this situation. What should your reasoning be?
“When diverting traffic in connection to roadworks, it is common to use yellow road markings. These markings take priority over other markings.” (STR’s Vägmärken & vägmarkeringar [Road Signs & Markings], 6th Edition, page 30)
The first alternative is true in the sense of a general statement, but not as the answer to this question. “Obstacle” refers to a crashed car or dropped cargo, not diversions that have been planned and carried out by road workers (which appears to be the case here).
More examples of explanations: